Decay dynamics of the unbound ${}^{25}$O and ${}^{26}$O nuclei

Abstract

We study the ground and excited resonance states of ${}^{26}$O with a three-body model of ${}^{24}$O+n+n taking into account the coupling to the continuum. To this end, we use the new experimental data for the invariant mass spectroscopy of the unbound ${}^{25}$O and ${}^{26}$O nuclei, and present an update of three-body model calculations for the two-neutron decay of the ${}^{26}$O nucleus. With the new model inputs determined with the ground state decay of ${}^{26}$O, we discuss the di-neurtron correlations and a halo nature of this nucleus, as well as the structure of the excited states. For the energy of the 2${}^{+}$ state, we achieve an excellent agreement with the experimental data with this calculation. We show that the 2${}^{+}$ state consists predominantly of the $(d_{3/2}{)}^2$ configuration, for which the pairing interaction between the valence neutrons slightly decreases its energy from the unperturbed one. We also discuss the structure of excited 0${}^{+}$ states of the ${}^{26}$O nucleus. In particular, we show the existence of an excited 0${}^{+}$ state at 3.38 MeV, which is mainly composed of the $(f_{7/2}{)}^2$ configuration.

12 pages, 13 figures. To appear in Phys. Rev. C

References in corpus (4)

• Spin-orbit splitting and the tensor component of the Skyrme interaction
• Generic strong coupling behavior of Cooper pairs in the surface of superfluid nuclei
• Three-body correlations in the ground-state decay of 26O
• Three-body model calculation of the 2${}^{+}$ state in ${}^{26}$O

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